The present invention relates to dicing saws in general and, in particular, to dicing saws for dicing BGA (ball grid array) type package panels.
Dicing saws for a variety of purposes, in particular for dicing and singulation of BGA type package panels, are well known in the art. These saws generally include a reciprocating carriage which passes under a rotating saw blade held by a spindle. The carriage is slidably mounted on a slide for movement along a pair of tracks. Cooling water is sprayed onto the blade during dicing, and collects in two channels in the bottom of the housing of the dicing machine, one on each side of the carriage. One channel includes a water outlet, and the second channel is connected to the first for drainage.
In order to protect the slide from the cooling water sprayed on the saw blade and from scrap and debris from the sawing process, a bellows is provided extending over the tracks from the carriage to the housing which folds and expands as the carriage reciprocates along the tracks. However, it has been found that conventional bellows do not provide sufficient protection for the slide. During the dicing process, small pieces, and occasionally singulated dice, fly off the package being cut, and fall between folds of the bellows. These pieces are very sharp and cut the bellows when the bellows close tightly on them during reciprocation of the carriage. Once the bellows have been cut, water and debris can fall through the bellows and damage the slide.
Other pieces of debris and some dice from the dicing process fall onto the carriage cover extending horizontally from the sides of the carriage, or into the water drainage channels. Those on the carriage cover remain there until removed manually. Some of the debris which falls into the drainage channels flows with the water into the drain, and can cause clogging. Most of the pieces remain in the dicing machine, in many different locations on the floor of the housing. In order to permit the dicing machine to function properly, it must be shut down every hour or two, and a worker must manually collect all the slivers, pieces, and other debris from the housing, and throw them away, and save any usable dice which have fallen into the housing. This is a time consuming, awkward and sometimes dangerous process, and requires shutting down the machine at very frequent intervals, often every hour.
Accordingly, there is a long felt need for an apparatus and method for automatically collecting debris from a dicing machine, and it would be very desirable to have such an apparatus and method which both protects the bellows cover and permits easy collection of debris falling to the sides of the carriage.
According to the present invention, there is provided an attachment for a dicing saw having a housing, a carriage mounted in the housing, a bellows coupled to the carriage, and at least one drainage channel in the housing, the attachment including a collector for automatically collecting debris and fallen dice during operation of the dicing saw.
According to one embodiment of the invention, the collector includes a bellows protecting cover and a receptacle coupled to the housing and arranged automatically to receive debris and fallen dice from the dicing saw during operation.
Further according to one embodiment of the invention, the collector further includes a sloping skirt coupled to each side of the carriage and angled downwards towards a drainage channel.
Still further according to one embodiment of the invention, the collector includes a sloping floor mounted in the drainage channel, ending adjacent the receptacle.
According to a preferred embodiment, the attachment further includes an inlet nozzle for pressurized fluid for urging fallen scrap, debris, and singulated dice into the drainage channel.
There is also provided a method for cleaning a dicing saw having a housing, a carriage mounted in the housing, a bellows coupled to the carriage, and at least one drainage channel in the housing, the method including the steps of automatically collecting debris and fallen dice in a collector during operation of the dicing saw.
According to a preferred embodiment, the step of collecting includes mounting a bellows protecting cover over the bellows, and causing debris falling on the bellows protecting cover to fall into a receptacle coupled to the housing.